I've been happiest with the Marriott chains for most consistency across their brands for business travel certainty......and the most options for redemptions---resorts or city hotels for vacations, ResInns for family, and those interstate interchange Fairfields for when you just need a night's sleep on a long holiday drive.

Just like airline programs, think about where you want to go/stay when redeeming......for many years my secondary program was Hyatt, but when relatives moved to another town, it's a HolInn Express that's nearest them, so earning 7 or 8 free nights on the IC/HI system became worthwhile!